1. Field of the Invention
The present invention relates to a substrate treatment method and a substrate treatment apparatus which are adapted to supply a water-containing liquid to a substrate held by a substrate holding/rotating mechanism while rotating the substrate.
2. Description of the Related Art
Substrate treatment apparatuses for use in production processes for semiconductor devices and liquid crystal display devices include those of single substrate treatment type which are adapted to treat a single substrate at a time. Such a single-substrate treatment apparatus includes, for example, a spin chuck which rotates a substrate held thereon, a chemical nozzle which supplies a chemical to the substrate held on the spin chuck, and a deionized water nozzle which supplies deionized water to the substrate held on the spin chuck. With this arrangement, a chemical treatment process is performed by supplying the chemical to the substrate while rotating the spin chuck, then a rinsing process is performed by stopping the supply of the chemical and supplying the deionized water to the substrate while rotating the spin chuck for rinsing off the chemical from the surface of the substrate, and a drying process is performed by stopping the supply of the deionized water and rotating the spin chuck at a higher speed for spinning off the deionized water from the substrate.
In the rinsing process, the substrate is liable to be electrostatically charged due to friction between the substrate and the deionized water and between the deionized water and air, resulting in malfunction of devices formed on the substrate.
One approach to this problem is to reduce the amount of the charges on the substrate by using deionized water containing carbon dioxide gas dissolved therein in the rinsing process (see Japanese Unexamined Patent Publication (KOKAI) No. HEI9(1997)-1093).
However, further reduction of the substrate charge amount is demanded in the market. Unfortunately, it is impossible to meet the market demand simply by using the CO2-containing deionized water (carbonated water) in the rinsing process.